#!/bin/bash

# Sample script for the exec plugin (collectd-exec(5))
#
# This script uses smartctl(8) to read HDD temperatures. The drives are
# attached to a 3ware RAID controller which hddtempd can't handle.
# Unfortunately the smartmontools don't have a library so we can't write a
# C-plugin, at least not easily.
# Please note that only root can read the SMART attributes from harddrives,
# because special ``capabilities'' are necessary. However, the exec plugin will
# refuse to run scripts as root, which is why `sudo' is used here for
# fine-grained root privileges for the user `smart'. This isn't as straigt
# forward as one might hope, but we think that the gained security is worth it.

# The sudo configuration looks something like this:
# -- 8< --
# Cmnd_Alias      SMARTCTL = /usr/sbin/smartctl -d 3ware\,0 -A /dev/twe0, /usr/sbin/smartctl -d 3ware\,1 -A /dev/twe0, /usr/sbin/smartctl -d ata -A /dev/sda
# smart   ALL = (root) NOPASSWD: SMARTCTL
# -- >8 --

HOSTNAME="${COLLECTD_HOSTNAME:-`hostname -f`}"
INTERVAL="${COLLECTD_INTERVAL:-60}"

while sleep "$INTERVAL"
do
	TEMP=$((sudo smartctl -d 3ware,0 -A /dev/twe0 | grep Temperature_Celsius | awk '{ print $10; }') 2>/dev/null);
	if [ $? -ne 0 ]
	then
		TEMP="U"
	fi
	echo "PUTVAL $HOSTNAME/exec-smart/temperature-3ware_0 interval=$INTERVAL N:$TEMP"

	TEMP=$((sudo smartctl -d 3ware,1 -A /dev/twe0 | grep Temperature_Celsius | awk '{ print $10; }') 2>/dev/null);
	if [ $? -ne 0 ]
	then
		TEMP="U"
	fi
	echo "PUTVAL $HOSTNAME/exec-smart/temperature-3ware_1 interval=$INTERVAL N:$TEMP"

	TEMP=$((sudo smartctl -d ata -A /dev/sda | grep Temperature_Celsius | awk '{ print $10; }') 2>/dev/null);
	if [ $? -ne 0 ]
	then
		TEMP="U"
	fi
	echo "PUTVAL $HOSTNAME/exec-smart/temperature-sata_0 interval=$INTERVAL N:$TEMP"
done